USB protocol is a universal serial bus standard for connecting a host with a peripheral, being widely used in a host, such as a personal computer, a personal digital assistant, and a mobile computer, etc. It supports hot-plug, instant plug-and-play and bus power supply. Almost all peripherals such as a mouse, a keyboard, a game handler, a scanner, a digital camera, a printer, a hard disk, a security device, a disc, and a net card can connect to and communicate with a host by running a USB interface which has become a default interface between a peripheral and a computer.
In aspect of operating system platform support, Windows operating system such as Windows 98, Windows 2000, Windows XP, Windows Vista, and Windows 7, etc, Apple operating system, and Linux operating system all support USB interface. With increase in number of peripherals of a computer with USB interface, it requires a computer to be more supportable of a USB interface and USB device to be more efficient in identifying a host operating system.